1. Field of the Invention
This invention relates to high-frequency receivers and more particularly to receivers for the reception of television signals in the 2 to 2.5 GHz region.
2. Description of the Prior Art
As the use of television for entertainment and educational purposes has increased, the need for additional spectrum space has also increased in proportion. Partially, in an effort to meet this need, the Federal Communications Commission, in the early 1970's, set aside certain portions of the lower microwave region for metropolitan distribution of television signals for entertainment and education. The entertainment service known as MDS (Multipoint Distribution Service) has been assigned two "channels" between 2.15 and 2.16 GHz. Other channels in the same general region of the spectrum have been allocated for use by the educational service.
These services contemplate the use of a transmitter site in conjunction with widely spaced receiving sites. In the case of the MDS, the receiving sites typically correspond to CATV "head ends" or MATV receiver locations. Because of the potential widespread usage of the Multipoint Distribution Service and educational television, a market has developed for reliable, high quality, yet inexpensive television receivers operating in this frequency range.
In the past, military, governmental and common-carrier usage has generally dictated the design of microwave receivers. In general, such receivers have been built to standards which in many aspects are too exacting to permit economical mass production. For example, the machined waveguides, resonant cavities, micrometer-like tuning members, and the assorted "plumbing" utilized in many prior microwave receiver designs are often prohibitively expensive.
It is therefore an object of the present invention to provide a low-cost microwave television receiver utilizing no machined transmission line devices.
It is another object of the present invention to provide a microwave television receiver which utilizes "off-the-shelf" components and fabrication techniques which permit mass production.
It is yet another object of the present invention to provide a microwave television receiver of simplified design.